In recent years, on a site of work for counting the number of microorganisms or the like, media with easy handling and showing various kinds of forms, or various automated equipment have been widely applied. For example, Patent literature No. 1 discloses a sheet-form medium with easy handling. Moreover, Patent literature No. 2 discloses an apparatus for automatically fishing a bacterial colony. Moreover, Patent literature No. 3 and Non-patent literature No. 1 disclose a colony counter being an apparatus for automating counting of the number of microorganisms in food or the like, and for picking up culture media on which colonies grow by means of an image pickup apparatus to automatically count the number of microorganisms grown on the media by image analysis.